1. Field of the Invention
The present invention relates to an organic electroluminescent display and a demultiplexer, and more particularly, to an organic electroluminescent display comprising a demultiplexer having a plurality of demultiplexing circuits including a sample/hold circuit and a pre-charge switch.
2. Discussion of Related Art
An organic electroluminescent display uses the phenomenon of light of a particular wavelength emitted from excitons. Electrons and holes are injected through the cathode and anode of an organic thin-film and they recombine to form excitons. One of the features of an electroluminescent display is that it does not require extra sources of light, as opposed to the case with LCDs (liquid crystal display), because an organic electroluminescent display has self-emissive elements. Another feature for an organic electroluminescent display is that brightness of an organic electroluminescent device of an electroluminescent display is controlled by the amount of current flowing through the organic electroluminescent device.
There is a passive matrix method and an active matrix method in driving organic electroluminescent displays. In the passive matrix method, the anode and cathode are formed to cross at right angles and a line is selected to drive organic electroluminescent displays. While the advantages of an organic electroluminescent display driven by the passive matrix method include simple structure and relatively easy implementation, the problems with large screen implementations are high-energy consumption and decreased driving time for each emissive element. In the active matrix method, the amount of current flowing in an emissive element is controlled by using active elements. For an active element, a thin film transistor (labeled as “TFT” hereafter) is frequently used. The active matrix method is somewhat complex, but its advantages include low-energy consumption and prolonged light emission time (illumination period).
U.S. Pat. No. 6,787,249 to Satoshi Seo and titled ORGANIC LIGHT EMITTING ELEMENT AND LIGHT EMITTING DEVICE USING THE SAME, and incorporated herein, discusses organic light emitting elements that are bright and have low electric power consumption, and an organic light emitting device using the organic light emitting elements. Organic light emitting elements capable of converting triplet state excitation energy into light emission are manufactured by applying a binuclear complex having triplet excitation state electrons to the organic light emitting elements.
U.S. Pat. No. 5,852,425 to Neil Christopher Bird et al. and titled ACTIVE MATRIX DISPLAY DEVICES FOR DIGITAL VIDEO SIGNALS AND METHOD FOR DRIVING SUCH, and incorporated herein, discusses the use of sample-and-hold circuits following a demultiplexing of a data signal by demultiplexer when applying data to an active matrix display.
U.S. Pat. No. 5,781,167 to Thomas J. Rebeshi et al. and titled ANALOG VIDEO INPUT FLAT PANEL DISPLAY INTERFACE, and incorporated by reference, discusses the use of sample-and-hold circuits following a demultiplexing of a data signal by demultiplexer when applying data to a matrix display, such as an electroluminescent display panel.